Pfizer said on Tuesday that it has started an early-stage clinical trial of an experimental oral antiviral drug for Covid-19.
The New York-based company said the phase one study of the drug – called PF-07321332 – is being conducted in the United States. The drug is part of a class of drugs called protease inhibitors and works by inhibiting an enzyme that the virus needs to replicate in human cells.
Protease inhibitors are used to treat other viral pathogens, such as HIV and hepatitis C.
“Fighting the COVID-19 pandemic requires vaccine prevention and targeted treatment for those who contract the virus,” said Pfizer’s scientific director, Mikael Dolsten, in a press release. “Given the way in which SARS-CoV-2 is changing and the continued global impact of COVID-19, it seems likely that it will be critical to have access to therapeutic options now and after the pandemic.”
The test comes at a time when Pfizer is also working on an intravenously administered protease inhibitor, known as PF-07304814. This drug is currently in a phase 1b clinical trial in patients hospitalized with Covid-19.
A person passes by the Pfizer building in New York City, March 2, 2021.
Carlo Allegri | Reuters
Pfizer already has a vaccine authorized in the U.S. with German pharmaceutical company BioNTech, but health experts say the world will still need a variety of drugs and vaccines to end the pandemic, which has infected more than 29.8 million Americans and killed at least 542,991 in just over a year, according to data compiled by Johns Hopkins University.
The company said that preclinical studies have shown that the oral drug, the first protease inhibitor taken orally for Covid-19 to be evaluated in clinical studies, demonstrates “potent” antiviral activity against the virus.
Because it is taken orally, the drug can be used outside hospitals by people infected with the virus. The researchers hope the drug will prevent the disease from progressing and prevent people from being hospitalized.
Pfizer said it would provide more details about the drug at the Spring American Chemical Society meeting on April 6.